[DOC] multi_terms aggregation not supported in 1.3

[colbyham]

What do you want to do?

• Request a change to existing documentation
• Add new documentation
• Report a technical problem with the documentation
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Tell us about your request. Provide a summary of the request.
multi_terms aggregation is not supported but is listed as supported 1.3 multi_terms. Please remove this from the documentation.

*Version: List the OpenSearch version to which this issue applies, e.g. 2.14, 2.12--2.14, or all.
AWS managed 1.3 (OpenSearch_1_3_R20230928-P3)

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
Tested the issue with this example and got the same error github issue